Accelerator vacuum systems at MAX-lab

The paper describes briefly the present and future accelerator vacuum systems at MAX-lab, a national laboratory for synchrotron radiation and nuclear physics in Lund, Sweden. The present accelerator systems at MAX-lab, with the 500 MeV MAX I, the 1.5 GeV MAX II, and the 700 MeV MAX III storage rings, contain a variety of different vacuum pumps. In all three storage rings ion pumps and Titanium Sublimation Pumps (TSP) are used for obtaining a sufficiently good vacuum for the operation. In MAX II, two of the straight
section stainless steel vacuum chambers have been replaced with vacuum chambers made of an extruded Al profile with a Non Evaporable Getter (NEG) coating, allowing for smaller gaps of operation of the insertion devices installed at the straight sections. The NEG coated Al vacuum chambers work well and it is planned to equip two more straight sections in MAX II with NEG coated Al chambers during 2007. The 700 MeV storage ring MAX III, where 5 of 8 straight sections are made of NEG coated Al chambers, has been incommissioning during the past year and the design and the conditioning of the MAX III vacuum system is described in some detail.
MAX-lab plans for building a new accelerator facility called MAX IV, which will contain in total three storage rings at 0.7 GeV, 1.5 GeV and 3 GeV, and also a 3.5 GeV linear accelerator. A preliminary design of the vacuum system for the MAX IV 3 GeV storage ring, where effort has been spent on finding a cost efficient solution, is presented.